An iterative weighting method to apply ISR correction to e⁺e⁻ hadronic cross-section measurements

Abstract

Initial State Radiation (ISR) plays an important role in e⁺e⁻ collision experiments such as the BESIII. To correct the ISR effects in measurements of hadronic cross-sections of e⁺e⁻ annihilation, an iterative method that weights simulated ISR events is proposed here to assess the efficiency of event selection and the ISR correction factor for the observed cross-section. The simulated ISR events were generated only once, and the obtained cross-sectional line shape was used iteratively to weigh the same simulated ISR events to evaluate the efficiency and corrections until the results converge. Compared with the method of generating ISR events iteratively, the proposed weighting method provides consistent results, and reduces the computational time and disk space required by a factor of five or more, thus speeding-up e⁺e⁻ hadronic cross-section measurements.

Graphical abstract

Keywords

Initial State Radiation (ISR) / iteration / Monte Carlo weighting

References

[1] J. Blümlein, A. De Freitas, C. Raab, and K. Schön-wald, The O(α²) initial state QED corrections to e⁺e⁻ → γ^∗ /Z^∗₀, Nucl. Phys. B 956, 115055 (2020)

[2] J. Blümlein, A. De Freitas, C. G. Raab, and K. Schönwald, The effects of O(α²) initial state QED corrections to e⁺e⁻ → γ^∗ /Z^∗ at very high luminosity colliders, Phys. Lett. B 801, 135196 (2020)

[3] J. Blümlein, A. De Freitas, C. G. Raab, and K. Schönwald, The O(α²) initial state QED corrections to e⁺e⁻ annihilation to a neutral vector boson revisited, Phys. Lett. B 791, 206 (2019)

[4] G. Bonneau and F. Martin, Hard-photon emission in e⁺e⁻ reactions, Nucl. Phys. B 27(2), 381 (1971)

[5] D. R. Yennie, Comment on radiative corrections to e⁺e⁻ → ψ(3105), Phys. Rev. Lett. 34(4), 239 (1975)

[6] V. N. Baier, V. S. Fadin, V. A. Khoze, and E. A. Kuraev, Inelastic processes in high energy quantum electrodynamics, Phys. Rep. 78(3), 293 (1981)

[7] F. A. Berends and R. Kleiss, Initial state radiation for e⁺e⁻ annihilation into jets, Nucl. Phys. B 178(1), 141 (1981)

[8] E. A. Kuraev and V. S. Fadin, On radiative corrections to e⁺e⁻ single photon annihilation at high-energy, Sov. J. Nucl. Phys. 41, 466 (1985)

[9] O. Nicrosini and L. Trentadue, Soft photons and second order radiative corrections to e⁺e⁻ → Z⁰, Phys. Lett. B 196(4), 551 (1987)

[10] J. Ablinger, J. Blümlein, A. De Freitas, and K. Schönwald, Subleading logarithmic QED initial state corrections to e⁺e⁻ → γ^∗ /Z^∗ ₀ to O(α⁶L⁵), Nucl. Phys. B 955, 115045 (2020)

[11] G. Montagna, O. Nicrosini, F. Piccinini, and G. Passarino, TOPAZ0 4.0 — A new version of a computer program for evaluation of deconvoluted and realistic observables at LEP 1 and LEP 2, Comput. Phys. Commun. 117(3), 278 (1999)

[12] A. B. Arbuzov, M. Awramik, M. Czakon, A. Freitas, M. W. Grünewald, K. Mönig, S. Riemann, and T. Riemann, ZFITTER: A semi-analytical program for fermion pair production in annihilation, from version 6.21 to version 6.42, Comput. Phys. Commun. 174(9), 728 (2006)

[13] M. Ablikim, Z. H. An, J. Z. Bai, N. Berger, J. M. Bian, et al., Design and construction of the BESIII detector, Nucl. Instrum. Methods Phys. Res. A 614(3), 345 (2010)

[14] R. G. Ping, Event generators at BESIII, Chin. Phys. C 32(3), 599 (2008)

[15] Z. Deng, H. Liu, G. Cao, M. He, Y. Yuan, Z. You, and Y. Liang, BESIII simulation software, PoS ACAT, 043 (2007)

[16] M. Ablikim, et al. (BES Collaboration), Determination of the Ψ(3770), Ψ(4040), Ψ(4160) and Ψ(4415) resonance parameters, Phys. Lett. B 660, 315 (2008)

[17] M. Ablikim, et al. (BESIII Collaboration), Measurement of e⁺e⁻ → π⁺π ⁻ψ(3686) from 4.008 to 4.600 GeV and observation of a charged structure in the πψ(3686) mass spectrum, Phys. Rev. D 96, 032004 (2017)

[18] M. Ablikim, et al. (BESIII Collaboration), Precise measurement of the e⁺e⁻ → π⁺π ⁻J/ψ cross section at centerof- mass energies from 3.77 to 4.60 GeV, Phys. Rev. Lett. 118, 092001 (2017)

[19] M. Ablikim, et al. (BESIII Collaboration), Evidence of two resonant structures in e⁺e⁻ → π⁺π ⁻h_c, Phys. Rev. Lett. 118, 092002 (2017)

[20] M. Ablikim, et al. (BESIII Collaboration), Evidence of a resonant structure in the e⁺e⁻ → π⁺D⁰D ^∗− cross section between 4.05 and 4.60 GeV, Phys. Rev. Lett. 122, 102002 (2019)

[21] M. Ablikim, et al. (BESIII Collaboration), Study of e⁺e⁻ → γωJ/ψand observation of X(3872) → ωJ/ψ, Phys. Rev. Lett. 122, 232002 (2019)

[22] M. Ablikim, et al. (BESIII Collaboration), Cross section measurements of e⁺e⁻ → ωχ_c0 from s= 4.178 to 4.278 GeV, Phys. Rev. D 99, 091103 (2019)

[23] S. Actis, A. Arbuzov, G. Balossini, P. Beltrame, C. Bignamini, et al., Quest for precision in hadronic cross sections at low energy: Monte Carlo tools vs. experimental data, Eur. Phys. J. C 66(3–4), 585 (2010)

RIGHTS & PERMISSIONS

Higher Education Press